The aim of this research project is to describe the crucial tyrosine residues in the c-met receptor which are necessary for motogenesis (scattering) and morphogenesis (tubule formation) of epithelial cells in vitro. Signalling proteins which bind these specific residues via SH2 domains will be sought in order to delineate the sequence of signal transduction which leads to motility and tubule formation of epithelial cells in response to HGF. In order to study the HGF/c-met axis a met-/- epithelial cell line will be created. cDNA constructs of different mutant c-met receptors will be introduced into the knockout epithelial cell line and effects on chemotaxis and tubule formation in response to HGF will be observed. Once the crucial sequences required for these responses are discovered they will be used to find SH2 domain containing signalling proteins by screening recombinant DNA libraries made in expression vectors. The in vitro actions of epithelial cells in response to HGF, motogenesis (scattering) and morphogenesis (tubule formation), translate in vivo into the formation of 3 dimensional tubule structures during development, repair of renal tubules after injury, and invasion and metastases of tumor cells. Once intracellular signalling cascades are known, pharmacologic agents which agonize or antagonize these steps may be used to repair damaged renal tubules or decrease the metastatic potential of tumor cells.